Manchester City boss Manuel Pellegrini believes Joe Hart's injury-time penalty save to deny Lionel Messi has kept their Champions League hopes alive.
Luis Suarez's two first-half goals gave Barcelona a 2-0 lead before Sergio Aguero pulled a goal back.
Hart then denied Messi, although the Argentine spurned a great chance to score from the rebound.
"It was a very important save," said Pellegrini. "It would have been very difficult at 3-1."
The Chilean added: "It is not the best result to lose at home, but we will go to Barcelona to try to win. We still have the chance to do it."
Barcelona boss Luis Enrique refused to blame Messi, who has converted 44 of the 57 penalties he has taken for the La Liga club, for failing to find the net against City on Tuesday.
"Players who take penalties will always miss some, but we have full confidence in Messi," he said.
"We played a very complete game and we should be very satisfied with that. This was a very good display from our team. We were much better than our opponents."
City, who had defender Gael Clichy sent off late on after being awarded a second yellow card, will need to score at least twice at the Nou Camp on 18 March to have a chance of progressing to the quarter-finals.
Barcelona have only conceded two goals at home in a single game once this season - against Villarreal on 1 February - but still won 3-2.
"If we go to Barcelona and play in the way we normally do, like we did in the second half, then we will have chances," added Pellegrini.
"If we play in the way we can play, we can do it. When we have the ball, we must be the team we are every week in the Premier League."
Radio 5 live analysis - Barcelona far superior
Chris Waddle: "If you're going to play 4-4-2, you've got to hound the ball. City didn't do that and Barcelona just did whatever they wanted in the first half. Aguero and Dzeko, from the off, didn't pressurise people. Nasri got subbed and Silva didn't have the legs.
"Give credit to City, they stuck at it but you have to say Barcelona are far superior. Against 10 men, the visitors should have been thinking about going for another goal and Messi will be absolutely devastated with his penalty miss. He's a perfectionist."